My kids were told the reason they were being taught about the Holocaust was so “that it will never happen again”. I told them that is great, but it has happened again and worse - and keeps happening.
I forget all of the things I taught them about - but of course Stalin, Mao, Vietnam, Cambodia, Armenia, some places in Africa, etc. Israel wasn’t in the news at the time, but I should have included them as well.
One of my daughters did a report about the Holocaust when she was very young. A bunch of kids in her class said that she was making it up. The teacher told them that she was telling the truth, and that they would learn about it in a few more years.
A sensible teacher.